Diving cylinder with liner

ABSTRACT

A diving cylinder is lined with a plastic bag, and bag and cylinder are sealed to each other by annular members positioned in the neck portions of each with the bag annular member being seated inside the cylinder annular member so as to nest the bag neck therebetween.

I United States Patent [191 Travers et al.

[ Nov. 4, 1975 DIVING CYLINDER WITH LINER [75] Inventors: ArthurTravers, Corona del Mar;

Robert Leite, Garden Grove, both of Calif.

[73] Assignee: AMF Incorporated, White Plains,

[22] Filed: Mar. 15, 1974 [21] Appl. No.: 451,345

[52] US. Cl 222/3; 222/ 183; 220/63 R; 220/3 [51] Int. Cl. B65D 25/14[58] Field of Search 222/183, 3, 105, 5, 189, 222/92-95, 107, 386.5;220/3, 63 R, 85 B [56] References Cited UNITED STATES PATENTS 2,212,3188/1940 Gee 222/189 X 2,435,040 l/l948 Heidbrink et al 222/3 2,959,25011/1960 Minera.; 222/95 X l1/1960 Greenlee 220/3 UX 2,987,216 6/1961Fletcher 220/63 R X 3,081,905 3/1963 Schulze et a1 220/63 R 3,319,8375/1967 Mueller 222/386.5 X 3,672,543 6/1972 Roper et al. 222/1833,674,179 7/1972 Galloway 222/94 3,701,363 10/1972 Schuler et al 222/3 XFOREIGN PATENTS OR APPLICATIONS 1,022,104 3/1966 United Kingdom 222/95Primary Examiner-Robert B. Reeves Assistant ExaminerCharles A. MarmorAttorney, Agent, or FirmGeorge W. Price; Walter Lewis [57] ABSTRACT Adiving cylinder is lined with a plastic bag, and bag and cylinder aresealed to each other by annular members positioned in the neck portionsof each with the bag annular mernber being seated inside the cylinderannular member so as to nest the bag neck therebetween.

2 Claims, 2 Drawing Figures US. Patent 1 Nov. 4, 1975 FIG. I

DIVING CYLINDER WITH LINER This invention relates to a diving cylinderimprovement, and more particularly to a plastic bag lined tank and sealtherefor useful in air cylinders for divers.

ln diving cylinders it is important to keep moisture from reaching theinterior walls of the air tank to prevent rust corrosion and the like.It is an object of this invention to achieve that end, and otheradvantages, by providing an improved and low cost liner and seal for airdiving cylinders.

A preferred embodiment of the invention is illustrated in the drawings.

FIG. 1 is a broken away side view of the invention, and

FIG. 2 is an exploded view of the neck seal.

Shown in the drawings is a conventional air diving cylinder having anupper open neck portion 11 which is closed by a valve assembly 12 andseal 13. A plastic bag 14 lines the interior of the cylinder. The bag isconstructed from vinyl or other suitable plastic material. It ispreformed to be slightly oversize with respect to the cylinder and toconform to the interior thereof when inflated. Bag 14 has an upper openneck portion 15 and the cylinder and bag necks 11 and 15 are sealedclosed with respect to each other by a pair of annular members 16 and17. Members 16 and 17 are seated one within the other so as to nest thebag neck 15 therebetween. The valve assembly 12 has a dip tube 18depending therefrom into the bag lined cylinder, and a screen guard 19located in the annular member 17 extends therefrom to below the lowerend of the dip tube 18.

The inside of the cylinder neck is threaded and the exterior of theannular member 16 is also threaded so as to connect the annular member16 to the cylinder. Annular member 16 is a plastic material threadedbushing in the cylinder neck 11.

The bag annularmember 17 is a plastic plug positioned inside the bagneck 15. These two parts are connected together by heat sealing themtogether, or the like. The plastic plug 17 is sized so as to be seatedinside the bushing 16 with the bag neck 15 snug nested therebetween.

In the assembly of the device the bushing 16 is screw threaded intoplace, but this is not true of the plug 17. This provides the advantagethat the bag does not have to be twisted or turned in the cylinder, butmerely longitudinally inserted therein. Therefore, when a not shown airmandrel or pipe is inserted into the bag to inflate the same, it willnot encounter turns or wraps of the bag and possibly tear the same. Theair mandrel can be safely inserted to adjacent the bottom of the bag andstart inflating it from the bottom up. As the bag is inflated, any airor moisture between the bag and cylinder is driven out so that the bagclings to the interior surface of the cylinder. Thereafter, the plug 17is forced into the bushing 16 so that the bag neck 15 is nestedtherebetween so that the bag and cylinder neck portions are seal closedwith respect to each other. The lower end of plug 17 has a bevel 20 tomake it easy to force the plug 17 into place, and the upper end of plug17 has a lip 21 which catches on the bushing 16 so that the plug is notaccidentally forced through the bushing. If it is desired to inspect orreplace the bag, this is easily done merely by pulling the plug 17 fromits seated position in the bushing 16 and withdrawing the bag.

We claim:

1. In a metallic air diving cylinder, a plastic bag lining the interiorsurface of said cylinder, and sealing means for the upper ends of saidcylinder and bag to prevent ingress of moisture between said bag andcylinder, said cylinder having an upper open neck portion, said bagbeing slightly oversize with respect to said cylinder to conform theretowhen inflated, said bag having an upper open neck portion, said sealingmeans sealing said two neck portions together and comprising essentiallyan annular member connected to the inside of each of said neck portionsrespectively, the annular member which is inside the bag neck portionbeing seated in the other annular member whereby said bag neck portionis nested between said pair of annular members, the open neck portion ofsaid cylinder being internally threaded, the annular member which isconnected to the inside of said cylinder neck portion comprising anexternally threaded plastic bushing, the annular member which isconnected to the inside of said bag neck portion comprising a plasticplug, and said plastic plug and bag neck portion being heat sealedtogether.

2. In a diving cylinder as in claim 1, wherein a valve assembly having adepending dip tube is connected to the upper end of said cylinder neckportion, said valve assembly and upper cylinder end being seal closedwith respect to each other, said dip tube depending from said valveassembly through said plastic plug into said bag lined cylinder, and atubular screen guard positioned in said plastic plug and extendingtherefrom to below the lower end of said dip tube.

1. In a metallic air diving cylinder, a plastic bag lining the interiorsurface of said cylinder, and sealing means for the upper ends of saidcylinder and bag to prevent ingress of moisture between said bag andcylinder, said cylinder having an upper open neck portion, said bagbeing slightly oversize with respect to said cylinder to conform theretowhen inflated, said bag having an upper open neck portion, said sealingmeans sealing said two neck portions together and comprising essentiallyan annular member connected to the inside of each of said neck portionsrespectively, the annular member which is inside the bag neck portionbeing seated in the other annular member whereby said bag neck portionis nested between said pair of annular members, the open neck portion ofsaid cylinder being internally threaded, the annular member which isconnected to the inside of said cylinder neck portion comprising anexternally threaded plastic bushing, the annular member which isconnected to the inside of said bag neck portion comprising a plasticplug, and said plastic plug and bag neck portion being heat sealedtogether.
 2. In a diving cylinder as in claim 1, wherein a valveassembly having a depending dip tube is connected to the upper end ofsaid cylinder neck portion, said valve assembly and upper cylinder endbeing seal closed with respect to each other, said dip tube dependingfrom said valve assembly through said plastic plug into said bag linedcylinder, and a tubular screen guard positioned in said plastic plug andextending therefrom to below the lower end of said dip tube.